There are no in-line search suppressors and I did not make it to the tower today to replace that equipment I'll find out more about it on Monday
Sent from my iPhone > On Apr 24, 2015, at 14:45, Forrest Christian (List Account) > <[email protected]> wrote: > > That's entirely possible as well, but I figured the injector would have shut > down fast enough to prevent that as well. > >> On Apr 24, 2015 1:41 PM, "Ken Hohhof" <[email protected]> wrote: >> Is it possible he has some surge protectors in the path and those are what >> got blown, not the radios? >> >> From: Forrest Christian (List Account) >> Sent: Friday, April 24, 2015 2:36 PM >> To: af >> Subject: Re: [AFMUG] Packet flux question >> >> I actually do a very fast, software defined, overcurrent shutdown in the >> product of interest here. It's been a while since I worked on that code but >> it will shut down a short circuit in a few ms or so. >> >> The software defined part allows some flexibility in the shutdown which is >> important in that I also have to not shut down for inrush currents. The >> algorithm is such that if the overcurrent is small it shuts it down slower >> than a, large one. Roughly, it trips once a certain amount of excessive >> energy is seen. I'm guessing in this case the amount of energy we let >> through is more than the windings on the magnetics can handle. If I have >> time I'll grab a set of magnetics and see if I can characterize this. >> >> I'm also surprised that the 100 series radios died as well as they should >> appear as a dead short to the injector and have no magnetics on those pins >> to blow up. >> >>> On Apr 24, 2015 8:58 AM, "Chuck McCown" <[email protected]> wrote: >>> Forrest, please forgive me for even thinking this thought... but I wonder >>> how much current it takes to blow a phy transformer and how hard it would >>> be to have an over current shutdown. I have done over current shutdowns >>> before and have used those over current passive devices that self heal. >>> Polyfuse I think is the name.... >>> >>> Like you need more ideas... >>> >>> From: Craig House >>> Sent: Friday, April 24, 2015 5:26 AM >>> To: [email protected] >>> Subject: Re: [AFMUG] Packet flux question >>> >>> Thanks Forrest. It was a mix of 450 and 100 series. They all appear to >>> have been damaged. The only thing I get an Ethernet link light on is a >>> bh50 radio >>> >>> Sent from my iPhone >>> >>>> On Apr 24, 2015, at 05:06, Forrest Christian (List Account) >>>> <[email protected]> wrote: >>>> >>>> Hmm.. I love (not) autocorrect on android... port, not portal... But now >>>> I'm on a real computer and have a chance to re-read the original message, >>>> and think a bit... I think I need to change my final answer. >>>> >>>> If these were 100 series radios I'd say "that seems rather odd that this >>>> would cause a failure". BUT... I'm assuming these are 450 radios. >>>> >>>> With the 450, there's a ethernet transformer on each pair. To DC, this is >>>> effectively a short. Or since these are made with very thin wire you >>>> could probably more accurately call it a 'fuse'. So if you take a pair >>>> and put say the + lead of a 24V power source on one wire in the pair, and >>>> the return (-) on the other pair, you'd find that the wire in the >>>> transformer would melt, and would probably do so very quickly. This is >>>> *exactly* the wiring that the 320/430 radios used. In addition, there is >>>> every possibility that the current being drawn before melting is smaller >>>> than the amount of current needed by a real 320 or 430 radio on power on. >>>> So, when this got plugged in, there's a good chance that you melted the >>>> ethernet transformers. >>>> >>>> The good news is if this is what has happened, it should be a fairly easy >>>> fix by almost any electronic repair shop which knows how to rework surface >>>> mount boards - just remove the magnetics and replace them. >>>> >>>> Unless of course there was another cause. >>>> >>>> -forrest >>>> >>>> >>>>> On Thu, Apr 23, 2015 at 9:58 PM, Forrest Christian (List Account) >>>>> <[email protected]> wrote: >>>>> Due to the odd wiring the radios probably shorted out the overcurrent >>>>> protection in the injectors, turning off the portal and I'd not be >>>>> surprised if the radios are just fine. Especially if they were never >>>>> plugged into an already on injector. >>>>> >>>>> So we accidentally put sync injectors on to a din rail today that were >>>>> for the 320/430 radios. Oops >>>>> >>>>> Both of the injectors were powered by a 24 V 10 amp power supply >>>>> All of the radios that were plugged into those injectors no longer appear >>>>> to boot up which wouldn't surprise me if there had been a 56 V power >>>>> supply or 48 V power supply powering them. However since they were >>>>> powered by a 24 V power supply how could that have damaged the radios? >>>>> >>>>> Sent from my iPhone >>>> >>>> >>>> >>>> -- >>>> Forrest Christian CEO, PacketFlux Technologies, Inc. >>>> Tel: 406-449-3345 | Address: 3577 Countryside Road, Helena, MT 59602 >>>> [email protected] | http://www.packetflux.com >>>> >>>>
